The present invention relates to a gas-using water heater having a water pressure-controlled gas general switch, wherein the water pressure-controlled gas general switch is disposed outside the water heater and is combined with the original manually operated gas general switch to form a dual general switch.
A conventional gas-using water heater more or less has the problem of gas leakage, especially after a long period use of the water heater or when the water heater is improperly used. The gas leakage of the water heater will cause the waste of gas or even cause disaster.
Moreover, a conventional gas-using water heater is provided with only one manually operated gas switch located on a gas tube or a head portion of a gas container. A user is likely to forget to close such manually operated gas switch or not to desire to close the same.
Accordingly, a potential danger exists when using the conventional gas-using water heater.
In addition, in case the water heater is installed at a very high position such as a top floor or other sites provided with low water pressure, especially when bathing with a sprinkler, the water flow with low water pressure often cannot meet the actual requirement of the gas-using water heater. The conventional gas-using water heater is not provided with a pressurizing motor pump so that respecting the low water pressure site, the user must add a pressurizing motor pump to the water heater for acquiring the necessary water pressure. Furthermore, the conventional gas-using water heater is not provided with any device capable of automatically closing the general gas switch in case of a fire so that when a fire takes place, the gas-using water heater is likely to aid the fire.
The conventional gas-using water heater mainly includes a water supplying/discharging system, an electric control system, a burning system and a heat exchanging system. All these systems are received in a housing. The water heater is connected with external gas tube and water pipe. The water temperature and amount can be adjusted by means of an adjusting switch disposed on the housing. Several portions of the above systems which relates to the present invention are described as follows:
1. The water supplying/discharging system: PA0 2. Electric control system: PA0 3. The burning system:
Please refer to FIGS. 2, 13 and 14. A water supplying tube 20, a cold water discharging tube 37 and a hot water discharging tube 14 are disposed under the water heater. A Venturi controller 10 is disposed adjacent to the water supplying tube 20. The Venturi controller 10 is divided into an upper and a lower chambers which are communicated with each other by a small tube 69. An upper end of the small tube 69 is connected with the upper chamber while a lower end of the small tube 69 is connected with a Venturi tube 65. The upper and lower chambers are separated by a resilient partitioning board 74. The water is filled into the upper chamber through the small tube from the Venturi tube 65. The lower chamber is directly communicated with the water supplying tube 20. An aiding board 67 is disposed above the partitioning board 74 and a top needle 61 is connected above the aiding board 67 and extended through the Venturi controller 10 for pushing away a gas incoming main valve of the water heater. The main valve has a pressing key 34 extending outside the main valve for controlling an electric switch 35. Before the top needle 61 opens the main valve, a compression spring 52 and an airtight board 48 are used to seal the gas from flowing through the main valve. A water pipe-like pre-heater 21 and a heat exchanger 2 are disposed near a middle portion of the water heater.
The water enters the water heater through such a route that the water first flows through the Venturi controller 10 into the pre-heater 21 and then flows through the heat exchanger 2 to be discharged from the water discharging tube. The Venturi tube 65 can suck the water in the upper chamber so that after continuous suction, the amount of the water contained in the upper chamber is reduced and the water pressure thereof is lowered. In contrast with the upper chamber, the lower chamber is communicated with the water supplying tube and therefore the water pressure of the lower chamber is kept constant. As a result, the water pressure of the lower chamber is larger than that of the upper chamber and the resilient partitioning board 68 is pressed by the water in the lower chamber and bent upward, making the aiding board 67 and the top needle 61 pushed upward.
When the water is not further supplied, the Venturi tube 65 is free from water flow and loses the sucking ability. Therefore, the lower chamber reversely fills the water into the upper chamber through the small tube 69. After the upper chamber is filled up with water, the water pressure in the upper and lower chambers becomes balanced and the partitioning board 68 is released from pressing force and lowered to the original position. Meanwhile, the compression spring 52 urges the aiding board 67 and the top needle 61 to descend to their original position.
A 1.5 V cell is disposed in a cell box located under the water heater. A sensing electronic transformer 8 is connected with the cell box for increasing the 1.5 V input voltage to 12 KV output voltage. After the cell is connected, two spark needles of a positive and a negative electrodes of the sensing electronic transformer create spark to burn the gas.
An electric switch 35 is disposed above the Venturi controller 10 and controlled by the pressing key 34. When the pressing key 34 ascends, the electric switch 35 connects with the power source, while when the pressing key 34 descends, the power is cut off. When the power is connected, the cell continuously supplies power to the transformer 8, making the spark needles continuously spark. When the gas of a pilot burner 22 is burned, the transformer 8 creates singles to stop the spark needle from sparking.
The burning system includes a gas incoming main valve, a gas incoming subsidiary valve 26, a pilot burner 22, a gas injecting tube 6, a gas sleeve 28, a gas nozzle 72, a main oven 5, a gas cock 9 and a smoke-discharging funnel 15. When the top needle 61 biases open the main valve, the gas flows thereinto from external tube and on one hand goes through the fine tube 27 toward the pilot burner and on the other hand goes through another fine tube 27 toward the electromagnetic gas valve 60 and gas incoming subsidiary valve 26 to be discharged from the gas injecting tube 6. At this time, small amount of gas exists at the openings of the pilot burner and gas injecting tube 6 and a spark can ignite the gas.
The Venturi controller first makes the main valve open, permitting the gas to flow into the pilot burner 22 and gas injecting tube 6 from the external tube. However, due to the delay effect, the electric switch 35 is not connected with the power source for creating the sparks. Therefore, the gas incoming subsidiary valve 26 is also under the pressure of the gas which is accumulated on the surface of a resilient separating board 74, making the same bent rearward. A link rod fitted with a pulling spring is disposed on the separating board 74. An airtight board 71 is disposed at a head portion of the link rod in alignment with a gas inlet. Therefore, when the separating board 74 is bent, the link rod and airtight board 71 are moved forward against the pulling force of the spring to seal the gas inlet and prevent the gas from passing therethrough. At this time, no gas is injected from the gas nozzle.
When the Venturi controller 10 continuously makes the top needle 61 ascend, the main valve is continuously opened, permitting the gas to continuously flow thereinto from the external tube. When the top needle 61 ascends to a preset height, the electric switch is released from the control of the pressing key 34 and connected with the power source. At this time, the electronic transformer 8 via the spark needle ignites the gas of the pilot burner. Meanwhile, the electromagnetic gas valve 60 is powered to seal the gas inlet of the fine tube so that the subsidiary valve 26 is not supplemented with new gas and released from the gas pressure and the pulling spring pulls the link rod and airtight board 71 away from the gas inlet, permitting the gas to flow through the main valve and gas cock 73 and enter the gas sleeve 25 from the subsidiary valve 26 and then enter the main oven from respective nozzles. At this time, the gas of the pilot burner 22 is ignited and the gas injected from the main oven is ignited. Also, the remaining gas in the gas injecting tube is ignited and burned. The smoke is discharged from the smoke discharging funnel.